In industrial connector equipment, a large number of differing clamp bodies for screw terminals have proved themselves by the billions, and are the most frequently-used connector equipment. Clamp bodies for the electrical screw terminals consist as a rule of a clamp pocket with essentially U-shaped cross section (EP 0 334 975), or an approximately rectangular housing with at least one threaded part and/or a threaded hole, into whose threads a clamping screw may be threaded. The high clamp body may also be in the shape of a pull strap. All clamp bodies have in common the fact that they include a clamp body recess, hereafter referred to as a cavity that serves to receive the electrical conductor, whereby the conductor may consist of single-wire or multiple-wire (fine wire) conductors.
The electrical conductor is clamped within this cavity by means of the clamp screw. Clamping of the electrical conductor may also be achieved by means of a current bus or rail inserted between the clamp screw and the electrical conductor. In order to increase the clamping effect of the electrical conductor, the current rail may be textured on the side facing toward the electrical conductor. Also, the floor surface of the cavity of the clamp body may be textured. So, for example, clamp bodies for electro-technical screw terminals are known from EP 0 082 285 B1 and from DE 203 05 314 that include walls projecting inward within the cavity between which recesses are located.
These clamp bodies with textured recess floors are produced, for example, from stamped plate steel or copper alloys using forming equipment. In this type of clamp body, which is formed of several pieces corresponding to the above-mentioned tasks, the cavity-plate or pocket-plate thickness selected acts disadvantageously on the deformation of the oblique floor walls during loading by the clamp screw. These deformations lead to a clear reduction of permissible clamping forces, whereby secure clamping because of the setting of the conductor connection is not ensured.
An additional embodiment example of a conventional clamp body may be taken from the State of the Art, for example from the “CLIPLINE Terminal 2002” TN12 5123461/10.04.02-00 product catalog of the company Phoenix Contact & Co. KG. The clamp bodies shown therein made of a tension-crack corrosion-resistant high-value copper alloy possess a crosswise drilled hole oblique to the floor of the cavity for optimum affixing of electrical conductors. This hole is created by a metal-cutting procedure within the clamp body, and is a penetrating hole that passes obliquely through the entire clamp body. Such an embodiment example of State-of-the-Art clamp bodies produced by means of a metal-cutting procedure may be taken from FIG. 1. The hole perpendicular to the cavity aperture is so located that the surface in the floor of the cavity, as well as adjacent oblique surfaces that represent the connection to the side walls and which normally extend flat from the one side of the cavity aperture to the other side of the cavity aperture, are interrupted by the drilled hole. This interruption serves to texture the cavity in order to increase the clamping effect between the electrical conductor and the clamp body. The drilled hole passing through the clamp body in the area of the floor surface of the cavity weakens the sidewalls of the clamp body exceedingly, i.e., the forces arising from the tension moment of the clamp screw may act disadvantageously on the geometric shape of the clamp body. The hazard of plastic deformation exists along with that of having no stable clamping action. Further, positive function upon several actuations of the screw terminal cannot be ensured. The metal-cutting processing procedure thus acts disadvantageously on the mechanical strength of the clamp body.